This is going to sound ridiculous but I was testing on my first Mac and wanted to play around with this hidden user account feature. After following the notes on this thread and lowering the UID to below 500, I ran the terminal command stated above to add it to the Hidden list. Now, for the life of me, I can't figure out how to reverse the process so I can access the account again under Sys Preferences.

Any help would be greatly appreciated. I'm pulling my hair out in frustration.

Thanks!